Design and Multicondition Comparison of Two Outer-Rotor Flux-Switching Permanent-Magnet Motors for In-Wheel Traction Applications

This paper designs and compares two outer-rotor flux switching permanent-magnet (FSPM) motors, in which the two different PM topologies of the V-shape magnet and I-shape magnet are adopted respectively in their stator structures, namely, V-FSPM motor and I-FSPM motor. First, the design principles and motor topologies are introduced. Second, by using the comprehensive sensitivity method and sequential nonlinear programming algorithm, the two motors are optimized efficiently before comparison, where the torque and torque ripple are selected as the design objectives. And then based on the finite element analysis (FEA) method, the motor performances are evaluated in detail, such as back EMF, torque characteristics, and efficiency. To extensively explore the advantages of the two motors, the comparison work involving output torque, torque ripple, and PM usage efficiencies are further implemented under three different conditions. Finally, the two prototyped motors are manufactured and tested, respectively. The theoretical analysis is verified by the FEA results and experimental results, which reveals that both of the two motors can be interesting and potential candidates for the in-wheel traction applications.